In the past, a number of adjustable orthosis have been developed for attachment to the forearm and upper arm of a human subject to aid in the rehabilitation of an injured elbow joint. Generally, these known devices incorporate a hinge at the elbow joint which permits tensioned bending movement about the pivotal axis formed by the hinge. Orthotic braces of this pivotal type generally do not provide for rotational movement of the forearm about the elbow joint based on the muscles that connect the radius and the ulna. U.S. Pat. Nos. 5,031,606 to G. Ring and 5,167,612 to P. Bonnutti disclose orthotic devices of this known pivotal type.
Devices to assist in regaining pronation and supination motion at the wrist joint are also known to the prior art. U.S. Pat. No. 4,899,735 to K. Townsend et al. illustrates a torsion bar splint for the forearm which retains the forearm in a position to which it is rotated under the control of a patient or as assisted by a therapist. To return the forearm to a rest position, a tension release device may be actuated. This torsion bar splint holds the elbow in a 90.degree. position close to the body and provides no resistance to pronation or supination motion.